The argument about nuke's ability to swing is crazy (navy plants)... of course they can, but it requires different fuel loads than today when they try to base load. The crazy part is why would a utility swing the cheapest fuel cost plant in their system? Swing (down-power) the highest fuel cost plant first, and it probably ain't the nuke. The problem is being forced to buy the temporaries when available. And with big PWRs with B reactivity control, towards EOL swinging generates huge amounts of let-down waste chasing Xe. That waste processing cost has to be factored in. In a mostly nuke grid, like France, obviously some nukes are swinging... but those swing plants have fuel loaded to support it.